ConquerHub HTML validation

- Static HTML pages: 13
- Playground component cards: 46 (same order/category/component IDs as supplied reference)
- Full form appears before plain form
- Shared JS passes Node syntax validation
- Programmer PHP reference files pass php -l
- No PWA manifest or service-worker registration
- No SPA/hash router
- No missing local image/script/stylesheet references in generated HTML/theme CSS
- Theme stylesheets: Umbra, Eclipse, Nova
- Market and Guides intentionally have no standalone HTML page
- Browser target: Chrome desktop/mobile responsive CSS included

Note: headless Chromium screenshot rendering is not available reliably in this container because the Chromium process fails on its system DBus/network service. Static DOM, asset and syntax validation completed successfully.
